Pregnancy and pregnancy outcomes in a prospective cohort study: Final results from the Nexplanon Observational Risk Assessment Study (NORA)

ObjectivesTo monitor pregnancy occurrence and outcomes among Nexplanon users in the United States during standard clinical practice.Study designThe Nexplanon Observational Risk Assessment (NORA) study was a large prospective cohort study conducted in the United States (US). Study participants with a newly inserted Nexplanon implant were recruited by health care professionals (HCPs) who had completed the Nexplanon clinical training. Via a survey, study participants were followed up at 6-month intervals for 36 months and 6 months after implant removal. Reported unintended pregnancies were validated and classified as noninsertion, preinsertion, during-use, or postremoval.ResultsFour hundred and twenty-eight HCPs in 47 states recruited 7364 Nexplanon users. Pregnancies included one noninsertion, eight preinsertion, three during-use, and 14 postremoval pregnancies; of these 26 pregnancies, 22 resulted in the birth of a healthy child, two resulted in an induced abortion, one resulted in a spontaneous abortion, and one resulted in an ectopic pregnancy. Six pregnancies occurred during-use (n = 3) or within 7 days following implant removal (n = 3), yielding a Pearl Index of 0.04 (95% CI, 0.02-0.09).ConclusionsNexplanon is an effective contraceptive in real-world users; the Pearl Index was 0.02 (95% CI, 0.00-0.06) for during-use pregnancies, and 0.04 when including pregnancies that occurred within 7 days following implant removal.ImplicationsThis large real-world-use study indicates that Nexplanon is as effective as shown in the preapproval clinical trials.